Semiconductors, such as computers (central processing units: CPUs), transistors, and light emitting diodes (LEDs) in use generate heat. The generated heat could sometimes reduce the performance of electronic components. Such electronic components that generate heat are typically provided with radiators.
Conventional radiators are made of metal with high thermal conductivity. In recent years, more radiators are made of insulating thermally conductive resin compositions which have high flexibility in shape and facilitate reduction in weight and size of radiators. Such an insulating thermally conductive resin composition needs to contain a large amount of thermally conductive inorganic fillers in binder resin in order to increase in thermal conductivity. However, it is known that just increasing the content of the thermally conductive inorganic fillers causes various problems. For example, if the content of the thermally conductive inorganic fillers is just increased, the viscosity of the resultant resin composition not yet cured increases to significantly reduce formability and workability, causing molding failure. Moreover, the amount of inorganic fillers that can be blended is limited, and the resultant resin composition has insufficient thermal conduction in many cases.
There is a disclosed method to increase the thermal conductivity by forming a bicontinuous phase-separated structure using plural resins and localizing thermally conductive particles in one of the resin phases (see Patent Literature 1, for example).
Moreover, another highly thermally conductive resin composition is disclosed, in which thermally conductive fillers are dispersed in matrix resin and are connected with a low-melting point alloy (see Patent Literature 2, for example). Still another insulating thermally conductive resin composition is disclosed, which includes thermoplastic resin, magnesium oxide, metallic powder having a melting point of 500° C. or higher, and a low-melting point alloy having a melting point of 500° C. or lower (see Patent Literature 3, for example). A highly thermally conductive polymer nanocomposite material is disclosed, in which thermally conductive fillers supporting metallic nano-particles having a melting point of 240° C. or higher are dispersed in a resin composition (see Patent Literature 4, for example).
Moreover, a highly thermally conductive resin composition is disclosed which includes thermoplastic resin, a highly thermally conductive inorganic compound, and low-melting point glass (see Patent Literature 5, for example).